User blog comment:Dogepool/MANAPHY/@comment-31800919-20170718201201

Its because of the manaphy event alot of people has it now that its value lessen, so thats a reason why you mostly get bad trade and for competative people the usually want manaphy with Timid or Modest nature with 31 ivs in speed, so that they outspeed other manaphys. If your manaphy is not with this nature and ivs you can only find a good trade with people who are new and havent been on the event yet or people who just want it for the Pokedex.

For me If you get the manaphy with this ivs and Nature you can trade for some good legendaries like latios and latias or maybe even two, but that depends if the person is desperate, the manaphy is now only equilavent to a myhtical pokemon or 2 shinies if not having the said ivs and nature.